Liquefaction of Carbon DioxideDry ice is placed into an acrylic plastic cylinder. A valve is closed and pressure in the cylinder increases. When the pressure reaches 350 kPa (50 psi) it stops increasing and liquid CO2 appears.

Equilibrium |

Phases / Phase Transitions / Diagrams |

Physical Properties

Phase ChangesBy using a coolant at a temperature below the boiling point of the gases chlorine, bromine and iodine, the gases are condensed into liquid form.

Phases / Phase Transitions / Diagrams

Critical Point of BenzeneA sealed tube containing benzene liquid and vapor is heated. As the critical temperature is approached, the meniscus flattens. At the critical temperature the meniscus disappears, and separate liquid and vapor phases can no longer be detected.

Thermodynamics : EntropyPhaseChange (13 Variations)
Aluminum can be evaporated in a vacuum to form highly reflective coatings. Aluminum boils at 2792K and has a heat of vaporization of 70.0 kcal/mol. Calculate the entropy change for the vaporization of one mole of aluminum.

Thermodynamics |

Chemometrics |

Phases / Phase Transitions / Diagrams

Thermochemistry : PhaseChanges (8 Variations)
Steam at 100oC is condensed by an ice-water mixture at 0oC. Assuming that there is still ice present when the process is over, how much ice will be melted if 10.0 g of steam is condensed? The following may be useful:enthalpy of vaporization of water = 40.7 kJ/mol; enthalpy of fusion of water = 6.07 kJ/mol; specific heat capacity of water = 4.184 J/g•K.

EQVAPSIM: A Vapor–Liquid Equilibria of Binary Systems Computer Simulation by LabVIEWA. Belletti, R. Borromei, and G. InglettoReports the results of a program using LabVIEW software to simulate the construction of a phase diagram representing a liquidvapor equilibrium. The program models work in a real laboratory, including mistakes commonly made in this context.Belletti, A.; Borromei, R.; Ingletto, G. J. Chem. Educ.2008, 85, 879.

Equilibrium |

Thermodynamics |

Student-Centered Learning

Understanding the Clausius–Clapeyron Equation by Employing an Easily Adaptable Pressure CookerMonica Galleano, Alberto Boveris, and Susana PuntaruloDescribes a laboratory exercise to understand the effect of pressure on phase equilibrium as described by the ClausiusClapeyron equation. The equipment required is a pressure cooker adapted with a pressure gauge and a thermometer in the lid, allowing the measurement of the pressure and the temperature of the chamber containing the water heated until vaporization.Galleano, Monica; Boveris, Alberto; Puntarulo, Susana. J. Chem. Educ.2008, 85, 276.

General Chemistry Multimedia ProblemsDavid M. WhisnantGeneral Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.